diff --git a/app/activitypub/util.py b/app/activitypub/util.py
index 453e4058..7abacc29 100644
--- a/app/activitypub/util.py
+++ b/app/activitypub/util.py
@@ -382,6 +382,14 @@ def actor_json_to_model(activity_json, address, server):
             mods_url = activity_json['moderators']
         else:
             mods_url = None
+
+        # only allow nsfw communities if enabled for this instance
+        site = Site.query.get(1)    # can't use g.site because actor_json_to_model can be called from celery
+        if activity_json['sensitive'] and not site.enable_nsfw:
+            return None
+        if 'nsfl' in activity_json and activity_json['nsfl'] and not site.enable_nsfl:
+            return None
+
         community = Community(name=activity_json['preferredUsername'],
                               title=activity_json['name'],
                               description=activity_json['summary'] if 'summary' in activity_json else '',
diff --git a/app/community/routes.py b/app/community/routes.py
index 996b398c..a48ec74a 100644
--- a/app/community/routes.py
+++ b/app/community/routes.py
@@ -90,6 +90,11 @@ def add_remote():
             message = Markup(
                 'Type address in the format !community@server.name. Search on <a href="https://lemmyverse.net/communities">Lemmyverse.net</a> to find some.')
             flash(message, 'error')
+        if new_community is None:
+            if g.site.enable_nsfw:
+                flash(_('Community not found.'), 'warning')
+            else:
+                flash(_('Community not found. If you are searching for a nsfw community it is blocked by this instance.'), 'warning')
 
     return render_template('community/add_remote.html',
                            title=_('Add remote community'), form=form, new_community=new_community,
diff --git a/app/community/util.py b/app/community/util.py
index d2c3df79..9f69862f 100644
--- a/app/community/util.py
+++ b/app/community/util.py
@@ -54,10 +54,11 @@ def search_for_community(address: str):
                         community_data.close()
                         if community_json['type'] == 'Group':
                             community = actor_json_to_model(community_json, name, server)
-                            if current_app.debug:
-                                retrieve_mods_and_backfill(community.id)
-                            else:
-                                retrieve_mods_and_backfill.delay(community.id)
+                            if community:
+                                if current_app.debug:
+                                    retrieve_mods_and_backfill(community.id)
+                                else:
+                                    retrieve_mods_and_backfill.delay(community.id)
                             return community
         return None